To calculate the weekly return of each stock and standard deviation of each stock as at end of December 2020.

1.

Date		Open	High	Low	Close	Adj Close		Volume
1/1/2020		3.30	3.36	3.28		------		------
1/2/2020		2.90	2.95	2.82
1/3/2020		2.70	2.74	2.61
1/4/2020		2.07	2.19	2.03
1/5/2020		2.35	2.40	2.23
1/6/2020		2.66	2.77	2.46
1/7/2020		2.58	2.61	2.48
1/8/2020		2.28	2.29	2.20
1/9/2020		2.30	2.37	2.21
1/10/2020		2.05	2.13	2.04
1/11/2020		2.00	2.11	1.98
	1/12/2020	2.56	2.71	2.54